Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
In wireless communications, transmission techniques may be used to overcome communications problems such as, for example, fast fading due to multipath effects or interference among multiple users. To employ such transmission techniques, it may be useful to estimate characteristics of the wireless channel. Typically, in-band sensing techniques may be used to estimate the wireless channel characteristics. However, such in-band techniques may require a large computational overhead, additional devices to be added to the wireless device, and other difficulties.